For hair bleaching or dyeing, two-part bleaches or permanent hair dyes composed of a first component part containing an alkali agent and a second component part containing an oxidizing agent have been used widely. The oxidizing agent of the second component part is added in order to heighten the hair dyeing effect by utilizing the coupling reaction of an intermediate for an oxidation dye and at the same time, cause the hair to turn bright color by promoting oxidative decomposition of melanin granules in the hair. The alkali agent of the first component part is added in order to activate the oxidizing agent and thereby enhance the hair dyeing and bleaching effects. Not only to bleach the hair into a lighter color than the original color but also to dye the hair into a color different therefrom, it is necessary to bleach melanin and the other pigments sufficiently. The hair bleaching power usually depends on the amounts of the alkali and oxidizing agent. When the composition is used for such a purpose, both alkali and oxidizing agents must be incorporated in sufficient amounts.
It is the common practice to use ammonia or organic amine as the alkali agent and hydrogen peroxide as the oxidizing agent. Addition of these agents in a large amount to obtain necessary bleaching power, however, tends to cause damage to the hair or irritate the scalp, depending on their using amount.
As a conventional method for overcoming the above-described problem, provided are the use of 1,3-propanediamine (Japanese Patent Laid-Open No. Hei 5-246827), use of triazacyclononane (Japanese Patent Laid-Open No. 2002-255763), and the like. They however include the problem that in a mixture system for practical use, they cannot bring about satisfactory results in performance.
The present invention therefore provides a hair bleach composition and a hair dye composition, each having an excellent dyeing power, capable of dyeing the hair into beautiful bright color, and is less damaging to the hair and less irritating to the scalp.
Further, the present invention provides a novel additive to be incorporated for attaining the above-described object.